A:2a
B:±2a
C:
D:| 2a |
With strong __________ to go to Tsinghua University, he is working very hard.
观察锐角α的三角函数表,用不等号填空.
(1)sin20°____ sin35°____ sin70°____ sin82°;
(2)cos12°____ cos28°____ cos45°____ cos89°;
(3)tan5°____tan32°____ tan55°____ tan80°;